In general, a video server records program contents compression-coded by a predetermined method. In recent years, the MPEG-2 method is known as a standard method of compression coding.
In an MPEG-2 stream, a unit called a Group Of Pictures (GOP) is treated as an independently accessible minimum unit. The GOP is constituted of one or a plurality of pictures. A GOP constituted of only one I picture is called a single GOP. A GOP constituted of a plurality of pictures formed of an I picture, and P and/or B picture is called a long GOP.
Incidentally, in the conventional video server, when playback of first program contents composed of the single GOP is switched to that of second program contents composed of the long GOP, the user must wait until video data corresponding to the long GOP is buffered after the switching to the second program contents. Therefore, the playback of the first program contents might not be switched to that of the second program contents in a seamless manner.